Question Looking at a customer's "gaming PC" and the fan setup is making me doubt my sanity

[mikeymikec]

It's a "Fierce PC" (brand, even the PSU has been branded that). Fairly low to mid end gaming build circa 2019-2020, i5-9400F + stock heatsink, 1660 super gfx card, nothing else worthy of note / relevant to my question. It's got three 12cm fans in the front and one at the back, but I have a feeling that it's a very 'form over function' design because it's one of these glass panel jobbies with RGB etc, but the three fans at the front have a pane of glass in front of them and the only intake airflow potential that I can see are some ~0.5-1mm slits every ~0.5cm down the sides of the left/right sides of the case next to the fans (and the slits have about the same length as the fans), and the same might be the case beneath the front of the case too (I've stuck my fingers beneath the case at the front and can't feel an obvious gap).

It seems to me that the front fans can't do anything in terms of airflow, and even when the computer is idle with the side panel off, there are warm zones (e.g. between the right side of the board and the fans) with no feeling of airflow at all. I honestly wonder if I could switch off the front fans only and leave the back running whether it would make any difference to system temps.

It gives me the impression that sure someone could manufacture a case as utterly useless as this, but surely they wouldn't...?

Feeling the air near the fans, I'm honestly wondering if the front fans are actually generating more heat than they're helping to circulate air.

 

[In2Photos]

NZXT sold a ton of the H510 case that was exactly the same. It has a front glass panel and the fans are directly behind it. The fresh air comes from a vented section between the glass and the fans. So I can assure you that plenty of these types of cases exist and are sold really well.




That being said a 9400 and 1660 super don't need too much air to keep "cool". Sure a better case design could improve temps but those aren't power hungry components. Can the front glass be removed so you could test performance with it on and off?

 

[mikeymikec]

NZXT sold a ton of the H510 case that was exactly the same. It has a front glass panel and the fans are directly behind it. The fresh air comes from a vented section between the glass and the fans. So I can assure you that plenty of these types of cases exist and are sold really well.


View attachment 132809

That being said a 9400 and 1660 super don't need too much air to keep "cool". Sure a better case design could improve temps but those aren't power hungry components. Can the front glass be removed so you could test performance with it on and off?

Quite a few cases (like Be Quiet's range) have fans behind a solid front panel, but with reasonable venting on the left/right sides near the fans so it's a common enough design style, and one image from the nzxt 510 suggests that this vent here supplies airflow to the front fans:

(presumably that's where this (near) vent leads!), while not optimal it's at least something...

 

[mikeymikec]

A close-up image of the OP case, the size of the gaps looks deceptively large due to the close range but I'd say the gaps are slightly less than 1mm in size. I haven't checked the other side but it feels exactly the same with those struts sticking out approximately 2.5cm apart.



If this was an iGPU machine for average uses then a chassis fan with limited airflow potential wouldn't worry me that much (though I'd consider just leaving the fan unplugged or remove it entirely if it came with the case), but to stick three fans behind solid glass and that IMO is just absurd otherwise.

 

[In2Photos]

Yeah that's certainly not a great design. I think a lot of those companies just jump on the latest "hot" design and try to copy it without really putting in any real R&D and testing for things like temps. They sell based on looks alone.

While the NZXT case does have better ventilation than the case you mention it still wasn't great. The area of the vented section is a fraction of the area that 2 or 3 140mm fans take up so it still restricts the air flow quite a bit. The "Flow" series cases were released just for this reason. My son loved the look of the H5 and ended up getting the H510 Flow because of it on his first build.

I wonder what would happen if you reversed the direction of one of the fans on the front, like the middle one. Would it pull some air from the case and push it between the fans and glass and then the other fans would pull that air and force it back into the case? While it wouldn't be fresh air it could at least create air movement.

 

[mikeymikec]

I wonder what would happen if you reversed the direction of one of the fans on the front, like the middle one. Would it pull some air from the case and push it between the fans and glass and then the other fans would pull that air and force it back into the case? While it wouldn't be fresh air it could at least create air movement.

Maybe the glass plane will need a little windscreen wiper to wipe off the condensation 😛

 

[aigomorla]

well fans even blocked will still circulate air flow inside the case.
Albet it wont be ideal, like brining in cool air, it will still make equilibrium a lot faster in the temp case.

Is it efficient... no.. your wasting energy just to speed up equilibrium.
Will it help? probably... but not as efficiently for the reason above, because your just recirculating the air without replacing it.

Is it bad design?

Gaming PC's in GENERAL are bad design.
Why would you LED a board add heat because of poor heat sinks to incorporate the LED, that gets HOT after many hours of usage??
OH yeah.. bling.

So we overclockers always had this war of Bling Vs Performance... the topic which is probably older then most of you guys which came from Cars. Do you want that rice rocket? or sleeper? so to speak....

And the guys who won arent even those two.. but Car "STANCE" modification PEOPLE!! gamers want BLING and more BLING, and even MORE BLING. So performance is secondary as long as it can turn heads.

Incase u guys dont know what "stance" means:

Stance (vehicle) - Wikipedia

en.wikipedia.org

So why are cases designed like that?
Bling...

Why are fans placed like that where they dont do anything?
LED Mounting points for Bling.

Why does it sell?
People want the disneyland electical light parade going on inside there case, and do not care about performance, because those that do, build their pc's from scratch.

 

[mikeymikec]

well fans even blocked will still circulate air flow inside the case.
Albet it wont be ideal, like brining in cool air, it will still make equilibrium a lot faster in the temp case.

Is it efficient... no.. your wasting energy just to speed up equilibrium.
Will it help? probably... but not as efficiently for the reason above, because your just recirculating the air without replacing it.

I'm not remotely qualified to argue this point, but I wonder if front fans circulating 90% recycled air is to the functional detriment of the reasonably-placed rear exhaust fan. 3 derpy fans working against 1 fan does not sound like a good mix.

At least this case has a top vent (no fans there) so there isn't a potential third element going on of 3 fans vs 1 fan possibly encouraging warm air to plateau rather than be exhausted.

 

[aigomorla]

I'm not remotely qualified to argue this point, but I wonder if front fans circulating 90% recycled air is to the functional detriment of the reasonably-placed rear exhaust fan. 3 derpy fans working against 1 fan does not sound like a good mix.

if you read my last point ... no... its not meant for anything but to add LED mounting points inside the case and make it look pretty to sell.

Alienware was notorious for this... and it sold, because again... bling sells, even if its poor quality bling.

 

[mikeymikec]

if you read my last point ... no... its not meant for anything but to add LED mounting points inside the case and make it look pretty to sell.

Alienware was notorious for this... and it sold, because again... bling sells, even if its poor quality bling.

You won't get any argument from me about the detriment of product quality when form trumps function 🙂 My question was more about the science of airflow and just how counterproductive that fan setup really is.

 

[aigomorla]

You won't get any argument from me about the detriment of product quality when form trumps function 🙂 My question was more about the science of airflow and just how counterproductive that fan setup really is.

well then we can exam you case in a thermal dynamics aspect.

Will increasing equilibrium help with exhaust? You bet... because ur getting that couple C's internally and then exhausting it.

But does it work in a case design with a rear fan?
Only if your CPU fan is not exhausting to that fan directly.
You do not want to recirculate the CPU exhaust. NO definitely do not... or the GPU exhaust even.
So by doing so, you can in sense hurt your overall PC temps. Which is why we have ducted and directed air flow in server cases.

So in most case designs... no... unless ur running a iGPU, and your cpu is a mobile cpu... i do not think recirculating the air will be any beneficial because you will be super charging the equilibrium temp due to those super furnaces.

But if you dont have much heat load to begin with.. recirculating the air, so the much colder air mixes with the warmer air and makes it lower overall, does in theory help, but not with how PC cases are laid out and designed.

 

[BoomerD]

I have the Be Quiet! Dark Base Pro 900 Rev.2 case:




It’s the most closed up looking case I think I’ve had in 20 years, yet surprisingly, the odd mesh vents across the top, bottom, and front edges does a pretty decent job of venting heat. I can open the front door when I’m pushing things hard…but it doesn’t really make a big difference.